DAMO 3/8 inch Demi Bullnose Half Bullnose Roundover Medium Diamond Hand Profiler Router Bit Profile Wheel with 5/8-11 Thread for Granite Concrete Marble Countertop Edge

I used this to round over the edge of thermal bluestone that is sitting a little proud (as intended) of an adjacent catwalk. I attached the bit to my single-speed (i.e. high RPM) grinder and used a garden hose to keep the bit cool. The bit worked perfectly, and has tons of life left after using it on 10 linear feet of bluestone. I bought the “medium” grit bit which left the edge smoother than the face of the bluestone. If I were doing it again, I’d order the “coarse” grit bit which might be a little better for this application.

Only did 3 counter tops and a mantel, but it worked as intended. Not sure how it would do on more than that but it looks like it is still in good shape so I would not hesitate to continue using it and/or buy it again.

I'm giving this tool 5 stars because it has worked well for me. But after a few projects (many hours of use) it started wobbling due to a bad bearing. Not surprising when you think about how this tool is used, pressed up against the material at a 90 degree angle to the axis of rotation, with considerable pressure as you run it across the material you're shaping.Since the diamond cutter part is still good, I took it apart and replaced its 2 bearings, and it's back to work. FYI,the bearings are standard 6004-2RS and 6203-2RS bearings (top and bottom). Inexpensive and easy to replace.Seems to work well around 2000 rpm. Run plenty of water over the surface you're shaping, either with a standalone hose or use this bit in a specialty stone polishing tool that has built-in water feed.

I am tiling a shower with 12"x12" marble pieces. I needed many trim pieces of various sizes around the doorway, and many of the pieces needed two rounded edges. The local tile shop wanted $10 per edge, which would be $20 per tile piece. I needed to have about 50 edges rounded over, so I figured I would try doing it myself.I intended to use one of my angle grinders, but did not realize that they all run at a fixed speed greater than 10,000 RPM. This cutter suggest 3500-4000 RPM. So I bought an adapter from Damo "Core Bits Adapter / 5/8"-11 to 3/8" Shank / for Electric Hand Drills". My Dewalt drill runs at 2500 RPM. I set up a jig to hold the tiles and pump water across the surface, and proceeded to make my rough cuts.After rounding the edges with this tool, they are rough. I sanded them with my orbital sander, starting with 80 grit, then 120, 220, and 320. Then I finished up with a 600-grit emory paper. My tiles have a "honed" finish, rather than a "polished" finish. Had they been polished, I would have needed to do another pass or two with even finer grits.If I were doing it again, I would also get some diamond-grit sanding pads. I think they would last much longer than pads intended for sanding wood. I spent about $150 for the cutter, adapter, and sand paper, plus several hours of work. But I also modified my design as the installation progressed and could make appropriate trim pieces as I proceeded.

Made my own bull nose tile that will pay for the cost of the slow speed grinder and this bullnose router bit. You have to clamp your work down, use a flat faced plywood stock under the tile you want to bullnose for the roller to glide on and hold the tile back from the edge anywhere from 1/64 to 3/16. It will give you very different looking bullnose by doing this. Wear rain gear and don't flood the bit with water, turn on the water till it trickles out the bit, use the slowest speed you can and hold the side grinder dead flat on your work.Makita PW5001C 4-Inch Hook and Loop Electronic was the side grinder I purchased with the bit. It takes a bite out of your wallet but then when you see what 90' of bullnose costs the tool will pay for itself in the first use. Go slow and do not stop on the ends, but keep the same motion going. I used a scrap piece of tile a both ends of the one I was grinding to prevent rounding at the ends of the tile your working on. Takes practice and a steady sawhorse.

Very easy to use with wet angle grinder.

I'm a newbie contractor. I have a bathroom be made of natural Stone, and the edges of around 20-30ft were sharp and not so pretty.I started with a sample area at my garage just to get feel of it, and this bit does not disappoint! It goes through easily, don't add pressure just go with it for few rounds and eventually you will have your bullnose.The final product is rough, so you will need to buy interchangeable polishing bits.By the time I finished the polishing bits were all used up. However this bullnose grinder can do another 100ft easily, I don't see much wear on it.

This demi bullnose has literally saved me thousands upon thousands of dollars. No more having to send customers tile to specialists that want $2 a foot just for cutting a Demi nose on the sides... No more needing to purchase 15% of "excess" tile. With this bit, contractors really only need to buy 5% in excess tile. I'm not kidding when I say that it has saved me thousands. After deducting the tile specialists and all the money it entails dropping off and picking up from them and deducting the 10% in excess tile you would've spent... that's thousands in savings per JOB!